Merge tag 'mailbox-v5.20' of git://git.linaro.org/landing-teams/working/fujitsu/integration

Pull mailbox updates from Jassi Brar:

 - mtk:
     - use rx_callback instead of cmdq_task_cb

 - qcom:
     - add syscon const
     - add SM6375 compatible

 - imx:
     - enable RST channel
     - clear pending irqs

* tag 'mailbox-v5.20' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
  mailbox: imx: clear pending interrupts
  dt-bindings: mailbox: qcom-ipcc: Add SM6375 compatible
  mailbox: imx: support RST channel
  dt-bindings: mailbox: imx-mu: add RST channel
  dt-bindings: mailbox: qcom,apcs-kpss-global: Add syscon const for relevant entries
  mailbox: mtk-cmdq: Remove proprietary cmdq_task_cb